Condiments based on mustard are utilized principally in continental Europe and those preparations familiarly named mustard are generally constituted by grains of ground mustard in a flour (this flour may or may not be degreased), the grains being dispersed in aromatized vinegar in most cases. The mixture is then subjected to enzymatic fermentation for liberating the active principle (allyl isothiocyanate), then finally homogenizing and pulverizing the product until a more or less homogeneous paste takes place. This type of "mustard" is indeed distinguishable from dry, powdered mustard, utilized especially in Anglo-Saxon countries in which an aroma develops only upon mixing with water just before use.
The condiment "mustard" actually on the market (which includes diverse categories: sweet table mustard, medium strength mustard, strong mustard, mustard with horse radish, Dijon mustard, etc., according to the species of mustard grains and the additives) is a product having a density of about 1 and whose storage stability is not always exemplary. In some situations, the mustard tends to form distinct phases, a solid phase and a liquid phase, making same not very appetizing.
There have been many attempts to remedy this problem in commerce and simultaneously to produce a product with low density in accordance with the actual principles of other light products, such as caramel mousses, yogurt mousses.